[RFC PATCH 4/4] arm64:numa: adding numa support for arm64 platforms.
Ganapatrao Kulkarni
ganapatrao.kulkarni at caviumnetworks.com
Thu Sep 25 02:03:59 PDT 2014
Adding numa support for arm64 based platforms.
This version creates numa mapping by parsing the dt table.
cpu to node id mapping is derived from cluster_id as defined in cpu-map.
memory to node id mapping is derived from nid property of memory node.
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni at caviumnetworks.com>
---
arch/arm64/Kconfig | 33 +++
arch/arm64/include/asm/mmzone.h | 32 +++
arch/arm64/include/asm/numa.h | 41 ++++
arch/arm64/kernel/setup.c | 8 +
arch/arm64/kernel/smp.c | 2 +
arch/arm64/mm/Makefile | 1 +
arch/arm64/mm/init.c | 33 ++-
arch/arm64/mm/numa.c | 471 ++++++++++++++++++++++++++++++++++++++++
8 files changed, 617 insertions(+), 4 deletions(-)
create mode 100644 arch/arm64/include/asm/mmzone.h
create mode 100644 arch/arm64/include/asm/numa.h
create mode 100644 arch/arm64/mm/numa.c
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a409105..415ee53 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -142,6 +142,7 @@ config ARCH_THUNDER
select NET_VENDOR_CAVIUM
select SATA_AHCI
select SATA_AHCI_PLATFORM
+ select HAVE_MEMBLOCK_NODE_MAP if NUMA
config ARCH_VEXPRESS
bool "ARMv8 software model (Versatile Express)"
@@ -309,6 +310,38 @@ config HOTPLUG_CPU
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu.
+# Common NUMA Features
+config NUMA
+ bool "Numa Memory Allocation and Scheduler Support"
+ depends on SMP
+ ---help---
+ Enable NUMA (Non Uniform Memory Access) support.
+
+ The kernel will try to allocate memory used by a CPU on the
+ local memory controller of the CPU and add some more
+ NUMA awareness to the kernel.
+
+config ARM64_DT_NUMA
+ def_bool y
+ prompt "DT NUMA detection"
+ depends on ARM64 && NUMA && DTC
+ ---help---
+ Enable DT based numa.
+
+config NODES_SHIFT
+ int "Maximum NUMA Nodes (as a power of 2)"
+ range 1 10
+ default "2"
+ depends on NEED_MULTIPLE_NODES
+ ---help---
+ Specify the maximum number of NUMA Nodes available on the target
+ system. Increases memory reserved to accommodate various tables.
+
+config USE_PERCPU_NUMA_NODE_ID
+ def_bool y
+ depends on NUMA
+
+
source kernel/Kconfig.preempt
config HZ
diff --git a/arch/arm64/include/asm/mmzone.h b/arch/arm64/include/asm/mmzone.h
new file mode 100644
index 0000000..d27ee66
--- /dev/null
+++ b/arch/arm64/include/asm/mmzone.h
@@ -0,0 +1,32 @@
+#ifndef __ASM_ARM64_MMZONE_H_
+#define __ASM_ARM64_MMZONE_H_
+
+#ifdef CONFIG_NUMA
+
+#include <linux/mmdebug.h>
+#include <asm/smp.h>
+#include <linux/types.h>
+#include <asm/numa.h>
+
+extern struct pglist_data *node_data[];
+
+#define NODE_DATA(nid) (node_data[nid])
+
+
+struct numa_memblk {
+ u64 start;
+ u64 end;
+ int nid;
+};
+
+struct numa_meminfo {
+ int nr_blks;
+ struct numa_memblk blk[NR_NODE_MEMBLKS];
+};
+
+void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi);
+int __init numa_cleanup_meminfo(struct numa_meminfo *mi);
+void __init numa_reset_distance(void);
+
+#endif /* CONFIG_NUMA */
+#endif /* __ASM_ARM64_MMZONE_H_ */
diff --git a/arch/arm64/include/asm/numa.h b/arch/arm64/include/asm/numa.h
new file mode 100644
index 0000000..46d53fd
--- /dev/null
+++ b/arch/arm64/include/asm/numa.h
@@ -0,0 +1,41 @@
+#ifndef _ASM_ARM64_NUMA_H
+#define _ASM_ARM64_NUMA_H
+
+#include <linux/nodemask.h>
+#include <asm/topology.h>
+
+#ifdef CONFIG_NUMA
+
+#define NR_NODE_MEMBLKS (MAX_NUMNODES * 2)
+#define ZONE_ALIGN (1UL << (MAX_ORDER + PAGE_SHIFT))
+
+/*
+ * Too small node sizes may confuse the VM badly. Usually they
+ * result from BIOS bugs. So dont recognize nodes as standalone
+ * NUMA entities that have less than this amount of RAM listed:
+ */
+#define NODE_MIN_SIZE (4*1024*1024)
+
+#define parent_node(node) (node)
+
+/* dummy definitions for pci functions */
+#define pcibus_to_node(node) 0
+#define cpumask_of_pcibus(bus) 0
+
+const struct cpumask *cpumask_of_node(int node);
+/* Mappings between node number and cpus on that node. */
+extern cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
+
+void __init arm64_numa_init(void);
+int __init numa_add_memblk(u32 nodeid, u64 start, u64 end);
+void numa_store_cpu_info(int cpu);
+void numa_set_node(int cpu, int node);
+void numa_clear_node(int cpu);
+void numa_add_cpu(int cpu);
+void numa_remove_cpu(int cpu);
+#else /* CONFIG_NUMA */
+static inline void arm64_numa_init(void);
+static inline void numa_store_cpu_info(int cpu) { }
+static inline void arm64_numa_init() { }
+#endif /* CONFIG_NUMA */
+#endif /* _ASM_ARM64_NUMA_H */
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index edb146d..436b78d 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -424,6 +424,9 @@ static int __init topology_init(void)
{
int i;
+ for_each_online_node(i)
+ register_one_node(i);
+
for_each_possible_cpu(i) {
struct cpu *cpu = &per_cpu(cpu_data.cpu, i);
cpu->hotpluggable = 1;
@@ -460,7 +463,12 @@ static int c_show(struct seq_file *m, void *v)
* "processor". Give glibc what it expects.
*/
#ifdef CONFIG_SMP
+ if (IS_ENABLED(CONFIG_NUMA)) {
+ seq_printf(m, "processor\t: %d", i);
+ seq_printf(m, " [nid: %d]\n", cpu_to_node(i));
+ } else {
seq_printf(m, "processor\t: %d\n", i);
+ }
#endif
}
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 4743397..60120db 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -50,6 +50,7 @@
#include <asm/sections.h>
#include <asm/tlbflush.h>
#include <asm/ptrace.h>
+#include <asm/numa.h>
#define CREATE_TRACE_POINTS
#include <trace/events/ipi.h>
@@ -123,6 +124,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
static void smp_store_cpu_info(unsigned int cpuid)
{
store_cpu_topology(cpuid);
+ numa_store_cpu_info(cpuid);
}
/*
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
index 3ecb56c..4dda3d0 100644
--- a/arch/arm64/mm/Makefile
+++ b/arch/arm64/mm/Makefile
@@ -3,3 +3,4 @@ obj-y := dma-mapping.o extable.o fault.o init.o \
ioremap.o mmap.o pgd.o mmu.o \
context.o proc.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
+obj-$(CONFIG_NUMA) += numa.o
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 271e654..4b2bbb4 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -39,6 +39,7 @@
#include <asm/setup.h>
#include <asm/sizes.h>
#include <asm/tlb.h>
+#include <asm/numa.h>
#include "mm.h"
@@ -73,6 +74,20 @@ static phys_addr_t max_zone_dma_phys(void)
return min(offset + (1ULL << 32), memblock_end_of_DRAM());
}
+#ifdef CONFIG_NUMA
+static void __init zone_sizes_init(unsigned long min, unsigned long max)
+{
+ unsigned long max_zone_pfns[MAX_NR_ZONES];
+
+ memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+ if (IS_ENABLED(CONFIG_ZONE_DMA))
+ max_zone_pfns[ZONE_DMA] = PFN_DOWN(max_zone_dma_phys());
+ max_zone_pfns[ZONE_NORMAL] = max;
+
+ free_area_init_nodes(max_zone_pfns);
+}
+
+#else
static void __init zone_sizes_init(unsigned long min, unsigned long max)
{
struct memblock_region *reg;
@@ -111,6 +126,7 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
free_area_init_node(0, zone_size, min, zhole_size);
}
+#endif /* CONFIG_NUMA */
#ifdef CONFIG_HAVE_ARCH_PFN_VALID
int pfn_valid(unsigned long pfn)
@@ -129,9 +145,16 @@ static void arm64_memory_present(void)
{
struct memblock_region *reg;
- for_each_memblock(memory, reg)
+ for_each_memblock(memory, reg) {
+#ifdef CONFIG_NUMA
+ memory_present(reg->nid,
+ memblock_region_memory_base_pfn(reg),
+ memblock_region_memory_end_pfn(reg));
+#else
memory_present(0, memblock_region_memory_base_pfn(reg),
memblock_region_memory_end_pfn(reg));
+#endif
+ }
}
#endif
@@ -168,6 +191,11 @@ void __init bootmem_init(void)
min = PFN_UP(memblock_start_of_DRAM());
max = PFN_DOWN(memblock_end_of_DRAM());
+ high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
+ max_pfn = max_low_pfn = max;
+
+ if (IS_ENABLED(CONFIG_NUMA))
+ arm64_numa_init();
/*
* Sparsemem tries to allocate bootmem in memory_present(), so must be
* done after the fixed reservations.
@@ -176,9 +204,6 @@ void __init bootmem_init(void)
sparse_init();
zone_sizes_init(min, max);
-
- high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
- max_pfn = max_low_pfn = max;
}
#ifndef CONFIG_SPARSEMEM_VMEMMAP
diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
new file mode 100644
index 0000000..a5f4555
--- /dev/null
+++ b/arch/arm64/mm/numa.c
@@ -0,0 +1,469 @@
+/*
+ * NUMA support, based on the x86 implementation.
+ *
+ * Copyright (C) 2014 Cavium Inc.
+ * Author: Ganapatrao Kulkarni <gkulkarni at cavium.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/memblock.h>
+#include <linux/mmzone.h>
+#include <linux/ctype.h>
+#include <linux/module.h>
+#include <linux/nodemask.h>
+#include <linux/sched.h>
+#include <linux/topology.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+
+int __initdata numa_off;
+nodemask_t numa_nodes_parsed __initdata;
+
+struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
+EXPORT_SYMBOL(node_data);
+
+static struct numa_meminfo numa_meminfo;
+
+static __init int numa_setup(char *opt)
+{
+ if (!opt)
+ return -EINVAL;
+ if (!strncmp(opt, "off", 3))
+ numa_off = 1;
+ return 0;
+}
+early_param("numa", numa_setup);
+
+cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
+EXPORT_SYMBOL(node_to_cpumask_map);
+
+/*
+ * Returns a pointer to the bitmask of CPUs on Node 'node'.
+ */
+const struct cpumask *cpumask_of_node(int node)
+{
+ if (node >= nr_node_ids) {
+ pr_warn("cpumask_of_node(%d): node > nr_node_ids(%d)\n",
+ node, nr_node_ids);
+ dump_stack();
+ return cpu_none_mask;
+ }
+ if (node_to_cpumask_map[node] == NULL) {
+ pr_warn("cpumask_of_node(%d): no node_to_cpumask_map!\n",
+ node);
+ dump_stack();
+ return cpu_online_mask;
+ }
+ return node_to_cpumask_map[node];
+}
+EXPORT_SYMBOL(cpumask_of_node);
+
+int cpu_to_node_map[NR_CPUS];
+EXPORT_SYMBOL(cpu_to_node_map);
+
+void numa_clear_node(int cpu)
+{
+ cpu_to_node_map[cpu] = NUMA_NO_NODE;
+}
+
+/*
+ * Allocate node_to_cpumask_map based on number of available nodes
+ * Requires node_possible_map to be valid.
+ *
+ * Note: cpumask_of_node() is not valid until after this is done.
+ * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
+ */
+void __init setup_node_to_cpumask_map(void)
+{
+ unsigned int node;
+
+ /* setup nr_node_ids if not done yet */
+ if (nr_node_ids == MAX_NUMNODES)
+ setup_nr_node_ids();
+
+ /* allocate the map */
+ for (node = 0; node < nr_node_ids; node++)
+ alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
+
+ /* cpumask_of_node() will now work */
+ pr_debug("Node to cpumask map for %d nodes\n", nr_node_ids);
+}
+
+/*
+ * Set the cpu to node and mem mapping
+ */
+void numa_store_cpu_info(cpu)
+{
+ cpu_to_node_map[cpu] = cpu_topology[cpu].cluster_id;
+ cpumask_set_cpu(cpu, node_to_cpumask_map[cpu_to_node_map[cpu]]);
+ set_numa_node(cpu_to_node_map[cpu]);
+ set_numa_mem(local_memory_node(cpu_to_node_map[cpu]));
+}
+
+/**
+ * numa_add_memblk_to - Add one numa_memblk to a numa_meminfo
+ */
+
+static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
+ struct numa_meminfo *mi)
+{
+ /* ignore zero length blks */
+ if (start == end)
+ return 0;
+
+ /* whine about and ignore invalid blks */
+ if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
+ pr_warn("numa: Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
+ nid, start, end - 1);
+ return 0;
+ }
+
+ if (mi->nr_blks >= NR_NODE_MEMBLKS) {
+ pr_err("numa: too many memblk ranges\n");
+ return -EINVAL;
+ }
+
+ pr_info("numa: Adding memblock %d [0x%llx - 0x%llx] on node %d\n",
+ mi->nr_blks, start, end, nid);
+ mi->blk[mi->nr_blks].start = start;
+ mi->blk[mi->nr_blks].end = end;
+ mi->blk[mi->nr_blks].nid = nid;
+ mi->nr_blks++;
+ return 0;
+}
+
+/**
+ * numa_add_memblk - Add one numa_memblk to numa_meminfo
+ * @nid: NUMA node ID of the new memblk
+ * @start: Start address of the new memblk
+ * @end: End address of the new memblk
+ *
+ * Add a new memblk to the default numa_meminfo.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+#define MAX_PHYS_ADDR ((phys_addr_t)~0)
+
+int __init numa_add_memblk(u32 nid, u64 base, u64 size)
+{
+ const u64 phys_offset = __pa(PAGE_OFFSET);
+
+ base &= PAGE_MASK;
+ size &= PAGE_MASK;
+
+ if (base > MAX_PHYS_ADDR) {
+ pr_warn("numa: Ignoring memory block 0x%llx - 0x%llx\n",
+ base, base + size);
+ return -ENOMEM;
+ }
+
+ if (base + size > MAX_PHYS_ADDR) {
+ pr_warn("numa: Ignoring memory range 0x%lx - 0x%llx\n",
+ ULONG_MAX, base + size);
+ size = MAX_PHYS_ADDR - base;
+ }
+
+ if (base + size < phys_offset) {
+ pr_warn("numa: Ignoring memory block 0x%llx - 0x%llx\n",
+ base, base + size);
+ return -ENOMEM;
+ }
+ if (base < phys_offset) {
+ pr_warn("numa: Ignoring memory range 0x%llx - 0x%llx\n",
+ base, phys_offset);
+ size -= phys_offset - base;
+ base = phys_offset;
+ }
+
+ node_set(nid, numa_nodes_parsed);
+ return numa_add_memblk_to(nid, base, base+size, &numa_meminfo);
+}
+EXPORT_SYMBOL(numa_add_memblk);
+
+/* Initialize NODE_DATA for a node on the local memory */
+static void __init setup_node_data(int nid, u64 start, u64 end)
+{
+ const size_t nd_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
+ u64 nd_pa;
+ void *nd;
+ int tnid;
+
+ /*
+ * Don't confuse VM with a node that doesn't have the
+ * minimum amount of memory:
+ */
+ if (end && (end - start) < NODE_MIN_SIZE)
+ return;
+
+ start = roundup(start, ZONE_ALIGN);
+
+ pr_info("Initmem setup node %d [mem %#010Lx-%#010Lx]\n",
+ nid, start, end - 1);
+
+ /*
+ * Allocate node data. Try node-local memory and then any node.
+ */
+ nd_pa = memblock_alloc_nid(nd_size, SMP_CACHE_BYTES, nid);
+ if (!nd_pa) {
+ nd_pa = __memblock_alloc_base(nd_size, SMP_CACHE_BYTES,
+ MEMBLOCK_ALLOC_ACCESSIBLE);
+ if (!nd_pa) {
+ pr_err("Cannot find %zu bytes in node %d\n",
+ nd_size, nid);
+ return;
+ }
+ }
+ nd = __va(nd_pa);
+
+ /* report and initialize */
+ pr_info(" NODE_DATA [mem %#010Lx-%#010Lx]\n",
+ nd_pa, nd_pa + nd_size - 1);
+ tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
+ if (tnid != nid)
+ pr_info(" NODE_DATA(%d) on node %d\n", nid, tnid);
+
+ node_data[nid] = nd;
+ memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
+ NODE_DATA(nid)->node_id = nid;
+ NODE_DATA(nid)->node_start_pfn = start >> PAGE_SHIFT;
+ NODE_DATA(nid)->node_spanned_pages = (end - start) >> PAGE_SHIFT;
+
+ node_set_online(nid);
+}
+
+/*
+ * Set nodes, which have memory in @mi, in *@nodemask.
+ */
+static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
+ const struct numa_meminfo *mi)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
+ if (mi->blk[i].start != mi->blk[i].end &&
+ mi->blk[i].nid != NUMA_NO_NODE)
+ node_set(mi->blk[i].nid, *nodemask);
+}
+
+/*
+ * Sanity check to catch more bad NUMA configurations (they are amazingly
+ * common). Make sure the nodes cover all memory.
+ */
+static bool __init numa_meminfo_cover_memory(const struct numa_meminfo *mi)
+{
+ u64 numaram, totalram;
+ int i;
+
+ numaram = 0;
+ for (i = 0; i < mi->nr_blks; i++) {
+ u64 s = mi->blk[i].start >> PAGE_SHIFT;
+ u64 e = mi->blk[i].end >> PAGE_SHIFT;
+
+ numaram += e - s;
+ numaram -= __absent_pages_in_range(mi->blk[i].nid, s, e);
+ if ((s64)numaram < 0)
+ numaram = 0;
+ }
+
+ totalram = max_pfn - absent_pages_in_range(0, max_pfn);
+
+ /* We seem to lose 3 pages somewhere. Allow 1M of slack. */
+ if ((s64)(totalram - numaram) >= (1 << (20 - PAGE_SHIFT))) {
+ pr_err("numa: nodes only cover %lluMB of your %lluMB Total RAM. Not used.\n",
+ (numaram << PAGE_SHIFT) >> 20,
+ (totalram << PAGE_SHIFT) >> 20);
+ return false;
+ }
+ return true;
+}
+
+static int __init numa_register_memblks(struct numa_meminfo *mi)
+{
+ unsigned long uninitialized_var(pfn_align);
+ int i, nid;
+
+ /* Account for nodes with cpus and no memory */
+ node_possible_map = numa_nodes_parsed;
+ numa_nodemask_from_meminfo(&node_possible_map, mi);
+ if (WARN_ON(nodes_empty(node_possible_map)))
+ return -EINVAL;
+
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *mb = &mi->blk[i];
+
+ memblock_set_node(mb->start, mb->end - mb->start,
+ &memblock.memory, mb->nid);
+ }
+
+ /*
+ * If sections array is gonna be used for pfn -> nid mapping, check
+ * whether its granularity is fine enough.
+ */
+#ifdef NODE_NOT_IN_PAGE_FLAGS
+ pfn_align = node_map_pfn_alignment();
+ if (pfn_align && pfn_align < PAGES_PER_SECTION) {
+ pr_warn("Node alignment %lluMB < min %lluMB, rejecting NUMA config\n",
+ PFN_PHYS(pfn_align) >> 20,
+ PFN_PHYS(PAGES_PER_SECTION) >> 20);
+ return -EINVAL;
+ }
+#endif
+ if (!numa_meminfo_cover_memory(mi))
+ return -EINVAL;
+
+ /* Finally register nodes. */
+ for_each_node_mask(nid, node_possible_map) {
+ u64 start = PFN_PHYS(max_pfn);
+ u64 end = 0;
+
+ for (i = 0; i < mi->nr_blks; i++) {
+ if (nid != mi->blk[i].nid)
+ continue;
+ start = min(mi->blk[i].start, start);
+ end = max(mi->blk[i].end, end);
+ }
+
+ if (start < end)
+ setup_node_data(nid, start, end);
+ }
+
+ /* Dump memblock with node info and return. */
+ memblock_dump_all();
+ return 0;
+}
+
+static int __init numa_init(int (*init_func)(void))
+{
+ int ret, i;
+
+ nodes_clear(node_possible_map);
+ nodes_clear(node_online_map);
+
+ ret = init_func();
+ if (ret < 0)
+ return ret;
+
+ ret = numa_register_memblks(&numa_meminfo);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < nr_cpu_ids; i++)
+ numa_clear_node(i);
+
+ setup_node_to_cpumask_map();
+ return 0;
+}
+
+/**
+ * dummy_numa_init - Fallback dummy NUMA init
+ *
+ * Used if there's no underlying NUMA architecture, NUMA initialization
+ * fails, or NUMA is disabled on the command line.
+ *
+ * Must online at least one node and add memory blocks that cover all
+ * allowed memory. This function must not fail.
+ */
+static int __init dummy_numa_init(void)
+{
+ pr_info("%s\n",
+ numa_off ? "NUMA turned off" : "No NUMA configuration found");
+ pr_info("Faking a node at [mem %#018Lx-%#018Lx]\n",
+ 0LLU, PFN_PHYS(max_pfn) - 1);
+
+ node_set(0, numa_nodes_parsed);
+ numa_add_memblk(0, 0, PFN_PHYS(max_pfn));
+
+ return 0;
+}
+
+/**
+ * early_init_dt_scan_numa_map - parse memory node and map nid to memory range.
+ */
+int __init early_init_dt_scan_numa_map(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+ const __be32 *reg, *endp, *nid_prop;
+ int l, nid;
+
+ /* We are scanning "memory" nodes only */
+ if (type == NULL) {
+ /*
+ * The longtrail doesn't have a device_type on the
+ * /memory node, so look for the node called /memory at 0.
+ */
+ if (depth != 1 || strcmp(uname, "memory at 0") != 0)
+ return 0;
+ } else if (strcmp(type, "memory") != 0)
+ return 0;
+
+ reg = of_get_flat_dt_prop(node, "reg", &l);
+ if (reg == NULL)
+ return 0;
+
+ endp = reg + (l / sizeof(__be32));
+ nid_prop = of_get_flat_dt_prop(node, "nid", &l);
+
+ if (nid_prop == NULL)
+ return -1;
+
+ nid = dt_mem_next_cell(OF_ROOT_NODE_ADDR_CELLS_DEFAULT, &nid_prop);
+
+ while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
+ u64 base, size;
+
+ base = dt_mem_next_cell(dt_root_addr_cells, ®);
+ size = dt_mem_next_cell(dt_root_size_cells, ®);
+
+ if (size == 0)
+ continue;
+ pr_debug("numa: nid %d , base %llx , size %llx\n", nid,
+ (unsigned long long)base,
+ (unsigned long long)size);
+ numa_add_memblk(nid, base, size);
+ }
+ return 0;
+}
+
+/* DT node mapping is done already early_init_dt_scan_memory */
+static inline int __init arm64_dt_numa_init(void)
+{
+ of_scan_flat_dt(early_init_dt_scan_numa_map, NULL);
+ return 0;
+}
+
+/**
+ * arm64_numa_init - Initialize NUMA
+ *
+ * Try each configured NUMA initialization method until one succeeds. The
+ * last fallback is dummy single node config encomapssing whole memory and
+ * never fails.
+ */
+void __init arm64_numa_init(void)
+{
+ if (!numa_off) {
+#ifdef CONFIG_ARM64_DT_NUMA
+ if (!numa_init(arm64_dt_numa_init))
+ return;
+#endif
+ }
+
+ numa_init(dummy_numa_init);
+}
--
1.8.1.4
More information about the linux-arm-kernel
mailing list